"Due to the disproportion between supply and demand on the market of aviation fuel, and a decrease in the minimal stock of fuel necessary for uninterrupted operation of the airports of the Moscow aviation hub and Koltsovo [Yekaterinburg], a threat of mass violations of passengers' rights has emerged," a PGO official said.

"The PGO ordered the Moscow and the Urals regions' transport prosecutors, and prosecutors of the Moscow and Omsk regions to check compliance with legislation in supplies of aviation fuel by oil refineries and transport organizations," the prosecutor added.